Within the discipline of ecology, the study of communities
and ecosystems presents unique difficulties for biology
instructors seeking to provide undergraduates with independent
or collaborative research opportunities. Investigations
in these areas typically require long-term or large field
studies and training in multiple disciplines. In the face
of global environmental problems, a strong ecology curriculum
also needs to provide the practical and intellectual tools
for students to examine the impact of humans on the environment
and search for solutions. This proposal seeks to enrich
the ecology curriculum at Swarthmore College by establishing
a long-term field study demonstrating the
mechanistic and experimental nature of ecological science
in which undergraduates can engage at all levels of instruction,
from freshman to senior year. The subject is forest
ecological stoichiometry. The setting is the Crum
Woods of Swarthmore College, a tract of 236 forested
acres (95 ha) adjacent to the College. We will investigate
the balance of multiple chemical elements, their influence
on tree species distribution and productivity, and their
effect on nutrient and carbon cycling at the ecosystem level.
In particular, students will gain an understanding of forest
carbon sequestration and its relevance to elevated levels
of atmospheric carbon dioxide.

This curricular initiative engages students in a genuine
experience with the scientific method. Teacher and student
will work side-by-side as co-researchers, investigating
open-ended questions with uncertain outcomes. The curriculum
will create opportunities to address incomplete or erroneous
ideas about the carbon and nutrient cycles. The field study
will be implemented across the curriculum, which includes
the introductory team-taught survey course Organismal and
Population Biology, an intermediate level Ecology course,
and the advanced independent research seminar Biodiversity
and Ecosystem Functioning.

Intellectual merits: Researchers
and modelers commonly make assumptions about the elemental
composition of plant tissues, because measuring its variability
within and among plants is expensive and time consuming.
Furthermore, soil, roots, and the organisms living belowground
are the hidden half of most terrestrial ecosystems, a significant
and understudied area of ecology. By characterizing species-specific
elemental composition and movement in the soil-plant-atmosphere
continuum, students will be contributing novel
and detailed data, enabling improvements in the quantification
of carbon and nutrient budgets in forest ecosystems. These
data will be of interest to those who study and model ecosystem
processes.

Broader impacts: The proposed
long-term field study will establish a framework for integrating
biogeochemical research into undergraduate courses and for
numerous and varied independent research and honors theses
in ecology. Student learning will focus on application of
the scientific method through collection, analysis, interpretation,
and presentation of publishable data using state-of-the-art
techniques and equipment typically limited to research universities.
Students will present their findings at intra-college symposia
and regional and national meetings. Course materials and
data developed in this project will be disseminated through
scientific and education meetings, journals and the Teaching
Issues and Experiments in Ecology (TIEE) web site. The student
body at Swarthmore includes approximately 32% domestic students
of color. Of students who enter anticipating a major in
science, about 28% are students of color and 48% are women;
however, a recent analysis of institutional data highlighted
poor retention within this group. This population may benefit
especially from the hands-on approach and collegial laboratory
environment created through this initiative. Furthermore,
the proposed study will create a bridge between the disciplines
of biology and chemistry for students with ecological interests
from programs including Biology, Environmental Studies,
and Engineering.